the birds hold coins. you have to do something to make them stay. then you kill them like normal monsters. For example the green bird will fly away if you do a double jump
I was able to dodge every shot but i ran into a stray shot with the 7th boss. I find it easiest to dodge with the power ship cause it is thin and has high attack power. the impossible is hard but i almost had it.
When you first go to Mardek's house and press X while going to the door a glitch will happen. Deugen will not be in your party and he will still talk as ERROR. You will fight monsters as only Mardek